You should not rinse at all after brushing your teeth as it washes away any benefit from the toothpaste. I can see that rubbing a bit back on would be a good idea.
As for ‘rinsing then spitting’ into the toilet bowl?
What a strange idea! Presumably it has water in it and is cleaned regularly with a good toilet cleaner?
And if you must spit into it then surely a quick flush would deal with it. Toilet bowls “see” a lot worse! 
What do you think about my situation?
Hair loss ....anyone with any advice please?


